package com.hmdp.service.impl;

import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONUtil;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.dto.Result;
import com.hmdp.entity.ShopType;
import com.hmdp.mapper.ShopTypeMapper;
import com.hmdp.service.IShopTypeService;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.List;

import static com.hmdp.utils.RedisConstants.CACHE_SHOP_TYPE_KEY;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class ShopTypeServiceImpl extends ServiceImpl<ShopTypeMapper, ShopType> implements IShopTypeService {

    @Resource
    private StringRedisTemplate stringRedisTemplate;
    @Override
    public Result queryTypeList() {
        // 1.从redis查询店铺列表数据
        String shopTypeJson = stringRedisTemplate.opsForValue().get(CACHE_SHOP_TYPE_KEY + "list");
        //2. 不存在，查询数据库
        if (StrUtil.isNotBlank(shopTypeJson)) {
            //3. 存在，直接返回
            System.out.println("从redis查询店铺列表数据"+shopTypeJson);
            //json转换成list
            return Result.ok(JSONUtil.toList(shopTypeJson, ShopType.class));
        }
        //4. 不存在，查询数据库列表
        List<ShopType> shopTypeList = query().orderByAsc("sort").list();
        //5. 数据库不存在，返回错误
        if (shopTypeList == null) {
            return Result.fail("店铺不存在！");
        }
        //6. 存在，写入Redis 列表类型转换成redis的string类型
        stringRedisTemplate.opsForValue().set(CACHE_SHOP_TYPE_KEY + "list", JSONUtil.toJsonStr(shopTypeList));
        //7.返回list
        return Result.ok(shopTypeList);
    }
}
